Negative pressure therapy has been utilized for the treatment of a variety of wounds by medical practitioners. Conventional negative pressure bandages are generally large in size and often require the use of complicated equipment such as suction pumps, vacuum pumps and complex electronic controllers to apply a negative pressure within the bandage to draw exudates and fluids away from the wound to a remote collection container. Typically, negative pressure therapy involves other associated equipment, such as the exudates/fluid collection canisters, liquid transporting conduits, and pressure regulators/transducers/sensors. As a result, negative pressure bandages and related equipment tends to be bulky and relatively costly. Such complexity typically requires professional placement of the bandage and connection to the pump and collection canister, followed by consistent, regular patient supervision and monitoring. Generally, negative pressure bandages are applied for approximately two days, at which time the bandage must be removed and replaced by professional technicians.
The rising costs of healthcare and of medical devices, such as negative pressure bandages, provide incentive to develop less expensive equipment, and procedures that are more easily utilized to reduce the costs associated with the use of sue therapy while improving on the effectiveness of the therapy. Simplification of the procedures and the equipment can allow in-home use of such therapies with a minimum of professional supervision and monitoring of the patients. Furthermore, patients continue to demand devices that are more easily portable to allow travel and mobility while utilizing the therapy.
In U.S. Pat. No. 7,615,036, granted to Ashok Joshi, et al on Nov. 10, 2009, a negative pressure bandage is disclosed in which the bandage has a housing that is sealed to the body surface of the patient and defines a liquid retention chamber coupled to a vacuum source to apply a negative pressure on the liquid retention chamber so that the exudates and fluids are drawn into an absorptive material within the liquid retention chamber. This liquid retention chamber is located adjacent to the wound from which the exudates and fluids are removed.
Improvements to negative pressure wound therapy devices can be found in U.S. Patent Publication No. 2009/0299251 of John Buan published on Dec. 3, 2009, to enhance the sealing of the bandage to the body surface of the patient. In this negative pressure wound therapy device, a vacuum is applied to a collection chamber in which an absorptive pad is disposed to collect the exudates and fluids drawn away from the wound by the vacuum (negative pressure). To enhance the connection of the tubing extending between the vacuum pump and the negative pressure therapy device, an extended length connector is disclosed, which will accommodate connection when ACE wrap or other coverings are applied to the exterior of the bandage.
In U.S. Pat. No. 7,361,184, granted on Apr. 22, 2008, to Ashok Joshi, an attempt to provide a self-contained negative pressure wound therapy device is provided so that the device does not require connection to a remote vacuum source. In this negative pressure wound dressing, an absorptive pad is also disposed in the fluid collection chamber, which is located adjacent the wound, the negative pressure drawing the exudates and fluids away from the wound into the absorptive pad. Several early embodiments of negative pressure bandages can be found in U.S. Pat. No. 5,636,643, granted to Louis Argenta, et al on Jun. 10, 1997, all of which, however, utilize a single chamber configuration in which a vacuum is applied to the fluid collection chamber and the exudates and fluid is drawn away through tubing to a remote pump and fluid retention chamber.
A micropump system provides the vacuum source for the negative pressure bandage disclosed in U.S. Patent Publication No. 2009/0264807 filed by Kurt Haggstrom and published on Oct. 22, 2009. This negative pressure dressing is also a single chamber configuration with an absorptive pad placed in contact with the wound while the micropump draws the exudates and fluids from the wound site into the absorptive pad. The micropump can be reusable or disposable. The outer housing layer of the bandage is provided with an opening that enables the absorptive pad to be removed and replaced on a periodic basis.
It would be desirable to provide a self-contained negative pressure bandage to centralize the collection and retention of exudates and fluid from a wound in a manner that removes the exudates and fluids away from the wound site without requiring transportation thereof to a remote retention chamber.